Do you... think heart surgery has become LESS dependent on surgical skill in the last 100 years? Cardiovascular surgeons spend MORE time in training now than they did 100 years ago.

Did heart surgery as we know it exist 100 years ago, or are you trying to conflate things to make a point?

"heart surgery" isn't a technique". Name something, literally anything connected to the profession, and tell me whether the training time is naturally bound to keep going up and up.